The instant invention relates to the field of dentistry and more particularly to a method of forming a tooth-like member having a shaped anatomical surface there.
Dental crowns have been widely used for many years to restore partially decayed or otherwise damaged teeth in the mouths of patients. In this connection, most dental crowns are made from molds or forms taken by dentists from the mouths of patients, and they are installed in the mouths of patients by dentists. However, for practical reasons, most crowns are actually fabricated in dental laboratories by laboratory technicians, although in some instances crowns are actually fabricated in the mouths of patients by dentists by applying dental composite materials over existing natural teeth.
The most common procedure for forming and installing a crown in the mouth of a patient is for a dentist to first form a mold of an existing tooth to which the crown is to be applied and to then prepare the existing tooth by removing the outer portions thereof in a grinding procedure to provide a prepared tooth of reduced size which is adapted to provide a base structure for receiving the crown thereon. A second mold is then taken of the prepared tooth, and thereafter the two molds are used to form a gold, metal, porcelain or castable ceramic crown which is dimensioned and configured to be received on the prepared tooth in the mouth of the patient. Finally, the finished crown is cemented to the prepared tooth to provide a restoration in the mouth of the patient which closely resembles the patient's original tooth.
Heretofore, one of the most common techniques for forming a dental crown has been to first form a wax pattern of the crown and to then form a gold, metal or castable ceramic crown from the wax pattern. In this connection, in order to form a wax pattern, a plaster or stone dye is first formed of the prepared tooth from a mold thereof taken from the patient's mouth, and a quantity of wax is applied to the dye to provide a wax form which has the general size and configuration of the desired crown. Next, a biting surface is established on the wax form by meshing it with an oppositing model tooth, an occlusal surface is carved in the wax form which resembles the anatomy of a natural tooth, and buckle, lingual, mesial and distal surfaces are carved and shaped in the form to provide a finished wax pattern which resembles the patient's natural tooth. Thereafter, a casting investment is formed around the wax pattern, the wax is burned from the investment, forming a void which is cast with gold, an approved metal, or castable ceramic, and the crown is polished or colored to provide a finished crown which can be assembled in the mouth of the patient by the dentist.
As an alternative to the above procedure, a crown can be made directly in a ceramic construction by first applying a metal coping to a die formed from a mold of the patient's prepared tooth. Thereafter, a formable porcelain or ceramic composition is applied to the metal coping and formed in the general configuration of the desired crown. A biting surface is then established on the porcelain or ceramic form, an occlusal surface is carved in the porcelain or ceramic form, and buckle, lingual, mesial and distal surfaces are also carved and formed in the porcelain or ceramic form. Finally, the form is fired and polished to provide a crown which has the general configuration of the patient's natural tooth.
While the above methods have generally been found to be effective for forming dental crowns, they have also been found to be relatively time consuming, and they have been found to require relatively high-skilled labor. Specifically, it has been found that it is generally extremely time consuming to carve anatomical surface configurations in the occlusal surfaces of wax, porcelain or ceramic forms for dental crowns.
The instant invention provides an improved method of forming a dental crown which does not require a time consuming, hand carving procedure to form an anatomical occlusal surface on the crown. Specifically, the instant invention provides an improved method of forming a tooth-like member having an anatomical occlusal surface configuration. Still more specifically, the preferred method of the instant invention comprises the steps of applying a formable material to a prepared tooth or a die thereof, establishing a biting surface in the formable material by meshing it with an opposing tooth, and pressing an occlusal surface having an anatomical configuration into the formable material utilizing a stamp having a complimentary anatomical surface pattern thereon. The preferred method further comprises the step of forming and shaping buckle, lingual, mesial and distal surfaces in the formable material in order to form it into a tooth-like member. The method of the subject invention can be effectively carried out to fabricate wax patterns, and it can also be applied directly to curable porcelain or ceramic composite materials in order to form dental crowns. When the method is applied to fabricate a wax pattern, a stamp, either cold or slightly heated, having an anatomical surface configuration thereon is pressed onto a warm, soft wax form in order to impart the desired occlusal surface configuration to the wax form. On the other hand, when the method is applied directly to a curable dental composite material, a nontoxic release agent, such as a vegetable oil, is preferably applied to the stamp before it is pressed onto the composite material so that the stamp can be more easily released. In any event, the method can be effectively utilized to form various tooth-like members; although, obviously, a different anatomical stamp must be utilized for each different type of tooth in order to form the appropriate occlusal surface configuration thereon.
It has been found that the method of the instant invention can be effectively utilized for forming dental crowns having anatomical occlusal surface configurations of consistently high quality and that it represents a significant advancement over the heretofore available methods of forming anatomical surface configurations. Specifically, it has been found that extremely well sculptured surface configurations can be quickly and easily applied to the occlusal surfaces of tooth like members by even relatively unskilled labor utilizing the method of the instant invention. Hence, the method of the instant invention makes it possible to substantially reduce the labor costs involved in the manufacturing of dental crowns, and it also makes it possible to assure consistently high quality in the occlusal surface configurations of dental crowns.
As a result of the above, it is a primary object of the instant invention to provide an effective method of forming an anatomical occlusal surface on a tooth-like member.
Another object of the instant invention is to provide an improved method of forming a dental crown.
An even further object of the instant invention is to provide a method of forming a dental crown which does not require skilled carving operations to form an anatomical configuration on the occlusal surface of the crown.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.